People with cirrhosis have a tendency to break down their stores of protein. The degree to which this occurs affects the rates of several complications of cirrhosis, including infection and bleeding into the gastrointestinal tract as well as survival after liver transplantation. The reason for this loss of protein stores is not known. An invariable finding in cirrhosis is an excess of the hormone glucagon. There is some evidence that glucagon causes protein breakdown. The purposes of this study are to determine the effect of cirrhosis on the metabolism of protein in the body, and to determine whether the changes in protein metabolism in cirrhosis are due to an excess of the hormone glucagon.